松树枯梢病菌菌株性状的变异

对来自国内外不同地区不同寄主的24个松树枯梢病菌菌株的培养性状、离体生长速率、产孢特性、分生孢子表面纹饰及致病性等方面的变异进行了比较研究。结果表明：菌株问的培养性状存在显著变异，国内17个菌株可分为两类，第1类菌丝平铺，第2类菌丝为绒絮状气生。国外7个菌株除上述两类，尚存在其他类型。光照和营养是影响产孢的两大重要因素，各菌株在全黑暗的PDA培养基上培养50d以后均产生厚垣孢子。各菌株在灭菌湿地松松针上的产孢量有明显差异。分生孢子表面纹饰与菌株类型无关。各菌株对供试3种松苗的致病性存在明显差异，大多数菌株能无伤直接侵入一至多个松种。大多数菌株在培养性状、离体生长速率、产孢量、分生孢子表面纹饰与致病性等性状之间无明显相关性。

Characteristics Differentiation of Sphaeropsis sapinea Isolates

24 isolates of Sphaeropsis sapinea obtained from various countries and hosts were studied on differences in cultural characteristics,growth rate in vitro,conidiospore production,conidial wall ornamentation and virulence.There were significant differences in cultural characteristics among isolates.17 Chinese isolates could be divided into two types,while alien isolates concluded more than two types.Light and nourishment were two important factors infecting conidiospore production.All the isolates produced chlamydospores after 50 days on PDA in dark.The amount of conidia produced on sterile pine needles differed significantly among isolates.The conidial wall ornamentation could not be linked to types of isolates.The results of inoculations showed obvious differences in virulence to three pine seedlings among isolates.Most isolates could infect unwounded seedlings.To most isolates,it didn't display an obvious link among these characteristics.